What are some alternatives?
When comparing Side Mirror App and Reflector, you can also consider the following products
Lookback USB - Capture the screen of any iDevice & record from mac camera.
LonelyScreen - AirPlay Receiver for PC/MAC. Cast iPhone/iPad screen to PC/MAC easily. Music, Movies and Screen Mirroring. Get started today. Cast AirPlay to PC/MAC.
AirServer - AirServer is a Mac and PC application that allows you to stream or mirror your Android device to your PC or Mac.
Mirroring360 - Mirroring360 offers a streamlined platform to wirelessly mirror iOS, Android, Windows, Mac and Chromebook screens.